Under high light intensities, if the ambient CO_2 concentration is...

Sugarcane, Maize, and Sorghum are $C_4$ plants, whereas Tomato is a $C_3$ plant.

$C_4$ plants show saturation in the rate of photosynthesis at about $360 \mu \mathrm{L} \mathrm{L}^{-1}$ of $\mathrm{CO}_2$. Therefore, increasing the $\mathrm{CO}_2$ concentration from $380 \mu \mathrm{L} \mathrm{L}^{-1}$ to $430 \mu \mathrm{L} \mathrm{L}^{-1}$ will not increase their photosynthetic rate, as they are already saturated.

$C_3$ plants respond to increased $\mathrm{CO}_2$ concentration and show saturation only beyond $450 \mu \mathrm{L} \mathrm{L}^{-1}$. Thus, as the $\mathrm{CO}_2$ concentration is gradually increased from $380 \mu \mathrm{L} \mathrm{L}^{-1}$ to $430 \mu \mathrm{L} \mathrm{L}^{-1}$, a $C_3$ plant like Tomato will exhibit a continuous increase in its rate of photosynthesis.

Answer: Tomato